Organised races are easy as they are provided at aid stations. My normal saturday run is usually my longest and is the one where calorie intake is needed. I've tried different solutions including carrying it all with me. Now I tend to park the car 'in the middle' of my run. Then I'll just do 2 hour loops from the car. The main item needed is water as its easily possible to carry enough calorie and electrolytes with you. I'm also currently living in Western Australia where is normally just hot and there isnt much water on the trails.
When it is not an organized run, you will have to manage water on your own. We have a 5km loop and we put our water bottles in a vehicle at the start point.
Depending on the distance that we plan to run, we increase/decrease the number of iterations of the loop.
When running in loops is not an option, people are advised to get a fuel belt.
